Transposition of the Great Arteries
(TGA)

Transposition of the great arteries (TGA) is the most common cyanotic (low blood oxygen) congenital heart defect.

Normally, the pulmonary artery comes off the right ventricle to pump deoxygenated (less oxygen content) blood to the lungs to get oxygen, while the aorta comes off the left ventricle to pump oxygenated blood from the lungs to the rest of the body.

In TGA, the arteries are switched. The aorta comes off the right ventricle and pumps deoxygenated blood to the body while the pulmonary artery comes off the left ventricle and pumps deoxygenated and oxygenated blood to the lungs.

To survive without intervention, there must be an additional defect that will allow the right and left side of the heart to communicate so that blood can mix. This defect can either be an atrial septal defect, ventricular septal defect, or a patent ductus arteriosus.  

This condition occurs predominantly in males, with a 90 percent mortality rate within the first year of life if left untreated. Like most congenital heart defects, the cause is unknown.

Symptoms of Transposition of the Great Arteries

Symptoms such as cyanosis, a bluish color to the skin, usually appear at birth or shortly after birth. The severity of the symptoms depends on the size and type of the defects and how much oxygen moves through the body.

Other common symptoms include:

TGA with no defect
Severe cyanosis within 24 hours of life
TGA with large ventricular septal defect (VSD)
Mild cyanosis when crying, increased breathing rate, increased heart rate, sweating, and failure to gain weight over the first six weeks of life
TGA with VSD and obstruction in left ventricle
Extreme cyanosis at birth
TGA with VSD and pulmonary artery obstruction
Progressive cyanosis from birth

Diagnosis of Transposition of the Great Arteries

Your UT Southwestern Medical Center doctor may perform several tests to diagnose transposition of the great arteries. Common diagnostic tests include:

Cardiac catheterization
Usually done for infants whose echocardiogram does not provide enough information on the heart’s anatomy
Echocardiography
A noninvasive test that shows TGA and may also show other defects in the heart
Hyperoxia test
Shows oxygen saturation in blood
Physical exam
To determine whether baby’s mouth and skin are blue or if heart murmur can be heard with a stethoscope

Transposition of the Great Arteries Treatment Options

Arterial switch surgery
Dividing pulmonary artery and aorta from wrong ventricles and attaching them to the correct ventricles; also transferring coronary arteries to allow the heart to receive proper blood flow
Balloon septostomy
Increasing hole size between the right and left atria to allow for more mixing of the blood
IV Prostaglandin E1
Making the patent ductus arteriosus stay open and allow more mixing of the blood

Request an Appointment

To schedule an appointment with a transposition of the great arteries expert at UT Southwestern's facilities in Dallas or for more information about our services, request an appointment or call 214-645-8300.